This invention relates to interproximal flossing devices, and more particularly to the drive mechanisms for interproximal flossing devices and the tip attachment structure associated therewith.
Available interproximal flossers employ a variety of tip movements to effect cleaning interproximal spaces formed between teeth. The tip movements typically include orbital, rotational, or linear movement. Rotational movement is typically created by a direct linkage between the tip and the drive shaft of a motor mounted in the handle. As the drive shaft rotates, the linkage and tip also rotate accordingly. Typically the rotation occurs in one direction, but can also be rotary oscillation. Rotation also occurs where the tip does not rotate about its longitudinal axis, but instead rotates about an axis offset from but generally parallel to the longitudinal axis of the tip. This Orbital tip movement is often created by using an off-center weight attached to the drive shaft of an electric motor mounted in the handle, which causes the entire device to move in an orbital manner in response to the off-center rotation of the weight. Orbital movement can be considered a subset of rotational movement because the tip rotates by moving along the orbital path.
Linear movement typically requires a linkage that converts the rotational movement of the motor drive shaft into linear oscillating movement at the tip. Oftentimes this structure for converting rotational to linear movement requires an offset cam surface mounted on the shaft of the motor with an end of the linkage attached thereto to follow the eccentric as it rotates. The end of the shaft is generally loosely engaged with the offset cam surface so that the shaft only moves in a direction to create linear motion at the tip end. In the linkage used to convert rotational movement to linear movement, there can be inefficiencies due to linkage connections (such as being loosely engaged), and difficulty in quietly connecting the linkage to the motor to avoid the creation of annoying sounds, due to loose connections, when the motor operates.
In addition, the tip connection structure typically used in interproximal flossing devices utilizes simple friction to attach the tip to the active end of the drive train. This type of connection is not secure, and can wear out and be less effective as the device is used.
It is with the above limitations of the presently available interproximal flossers that the invention described and claimed herein was developed.
The instant invention relates to a interproximal flossing device, and more particularly to the drive mechanism used in the device to create linear movement of the flossing tip. The interproximal flossing device of the present invention includes a link member that isolates lateral from vertical rotational movement to transfer only translatory arcuate movement. This is done by the combination of a hinge and pivot structure. A tip attachment structure is also included for secure placement of the tip on the link member, and allows easy removal and replacement. A tip member removal structure is also included to allow for easy removal of the tip member from the link member.
In one aspect of the invention, it includes a drive mechanism for an interproximal flosser having an electric motor with a rotating drive shaft, the drive mechanism comprising a link member having a first portion and a second portion, the first portion having a first end for attachment to the drive shaft in an off-center manner, and a second portion having a second end for receiving a tip member; a laterally-extending pivot axis formed on the link member; and a resiliently flexible hinge portion having a vertical bending axis formed on the link member. When the drive shaft rotates, the first end of the link member is rotated off-center from the drive shaft, creating vertical, lateral, and a combination of vertical and lateral movement, and the hinge isolating the non-vertical movement from the tip member while transmitting to the tip member vertical movement through the pivot, so that the tip member moves through a vertical arc.
In further detail, the hinge resiliently bends about a vertical axis to isolate the lateral movement from the tip member.
In additional detail, the hinge resiliently twists about its axial axis to isolate the non-vertical movement from the tip member motion.
In additional detail, the hinge resiliently bends about a vertical axis to isolate the lateral movement from the tip member, and the hinge resiliently axially twists about its axial axis to isolate the non-vertical movement from the tip member motion.
In further detail, the drive mechanism defined above further includes a drive member for attachment to the drive shaft, the drive member defining a recess positioned offset to the drive shaft; the first end of the link member is a ball; and the recess forms a socket for snugly rotatingly and pivotingly receiving the ball.
In another aspect of the invention, the drive mechanism includes a link member having a first portion and a second portion, the first portion having a first end, and a second portion having a second end for receiving a tip member; a means for attaching the first end of the link member to the drive shaft in an off-center manner; a laterally-extending pivot axis formed between the first and second portions; and a resiliently flexible hinge portion having a vertical bending axis formed on the link member. When the drive shaft rotates, the first end of the link member is rotated off-center from the drive shaft, creating vertical, lateral, and a combination of vertical and lateral movement, and the hinge isolating the non-vertical movement from the tip member while transmitting to the tip member vertical movement through the pivot, so that the tip member moves through a vertical arc.
There are several different means for attaching, including a cam and cam-follower structure, a ball and socket structure, a pair of gears, a pair of opposing flexible hinges, each having a laterally extending flexing axis formed on a sub-frame, a slider and slide channel having a substantially vertical motion, and a track cam surface for engagement with the first end of the link member.
In another aspect of the invention, an attachment structure for attaching a tip member to a link member of an automatic flosser includes a latch tab formed on the link member; and a latch recess formed on the tip member. When the tip member is positioned on the link member, the latch tab engages the latch recess.
In further detail, the tip member has a cup-shaped portion with an open end and an interior wall; the latch recess includes a pair of recesses positioned on the inner wall; and the latch tabs includes a pair of tabs formed on the link member to engage the corresponding latch recesses when the tip member is positioned on the link member.
In further detail, a space is formed between the link member and the inner wall of the cup-shaped portion to allow the cup shaped portion to be resiliently converted from a substantially circular form to a substantially oval shape to disengage the latch tabs from the latch recesses and remove the tip member from the link member.
In additional detail to the attachment structure as described above, the attachment structure includes a primary and secondary keying structure. The primary keying structure requires the tip member to attach to the link member in any of two orientations, with the two orientations including the width of the blade extending vertically. The secondary keying structure requires the tip member to attach to the link member in one orientation, the one orientation including the blade if curving upwardly or downwardly.
In another aspect of the invention, a structure for removing a tip member from a link member of an interproximal flosser includes a slot for receiving the tip member, the slot having side walls that converge along the length of the slot to engage and deform the tip member as the tip member is moved along the slot.
The foregoing and other features, utilities and advantages of the invention will be apparent from the following more particular description of a preferred embodiment of the invention as illustrated in the accompanying drawings.